This application claims priority under 35 USC 119 to German Patent Appl. No. 10 2015 102 352.0 filed on Feb. 199, 2015, the entire disclosure of which is incorporated herein by reference.
1. Field of the Invention
The invention relates to a method for monitoring a quiescent state in a motor vehicle. The present invention further relates to a corresponding apparatus in the form of a wake-up controller, to a corresponding computer program and to a corresponding storage medium.
2. Description of the Related Art
Various approaches for supplying a quiescent current to a control device in a motor vehicle can be found in the prior art. Some known control devices of this kind have a plurality of peripheral components. An example is an on-board charger (OBC) for connecting the traction battery of an electrically driven motor vehicle to the stationary power supply grid by means of a charging cable. Peripheral components of this kind can function to control or read back information. In the case of an on-board charger, the peripheral components may comprise plug connectors, pushbuttons or light-emitting diodes that have corresponding diagnosis resistors for forming information and for checking plausibility and for diagnosis purposes. Additionally, a “sleeping” motor vehicle is awaken by a wake-up controller and corresponding actions by a user. The user action may be the connection of a plug to the provided charging socket or pushing a pushbutton in the case of the on-board charger. Therefore, current has to be applied to all of the diagnosis resistors, and the read-back voltage has to be processed as an information carrier to decide whether the motor vehicle should be awaken. This results in a sharp increase in the quiescent current.
U.S. Pat. No. 6,198,995 proposes a method for operating a vehicle monitoring system that has inputs of a large number of vehicle subsystems. The vehicle is switched to a standby mode where normally no commissioning signals are applied to the inputs by the large number of vehicle subsystems. The inputs then are scanned for commissioning signals in recurring cycles. This scanning process is adjusted in terms of time over a predetermined time period. The time between the cycles from one scanning step to another is extended in response to a lack of commissioning signals at least at certain inputs in each predetermined time period for each preceding scanning step.
U.S. Pat. No. 6,674,762 states that, in an electronic system for transmitting data between a number of stations, partial system operation is possible by suitable selection of signal levels and wake-up levels, so that some of the stations can communicate with one another, while other stations are in a quiescent mode and save power.
EP 0 571 718 B1 discloses a circuit for standby operation of a functional group in a vehicle. The functional group is formed from a control device, sensors and actuators. The circuit supplies voltage to the functional group and to keep certain ranges of functions activated and/or to activate certain ranges of functions and to block other ranges of functions when the vehicle is turned off and standby operation is activated. Automatic deactivation of standby operation is provided after a predefined time or given predefined sensor values that indicate, for example, depletion of the energy supply.
U.S. Pat. No. 7,183,896 B2 and KR 10-1131526 relate to further relevant methods, apparatuses, control systems and media.
The invention provides a method for monitoring a quiescent state in a motor vehicle, a corresponding apparatus, a corresponding computer program and a corresponding storage medium.
Adaptive control is provided by the wake-up controller in the control device by having the wake-up controller select a peripheral component in a selective and event-controlled manner and checking only individual peripheral components.
The quiescent current can be reduced significantly by automatically identifying and selecting the peripheral components of the control device using the wake-up controller.
This solution provides particular advantages when an on-board charger of the generic type is used. For example, if no plug is plugged into the charging socket, no peripheral component is checked; if a charging plug is plugged into the charging socket but there is no control signal/CP signal, only one peripheral component is checked.
An exemplary embodiment of the invention is illustrated in the drawings and will be described in greater detail in the text that follows.
The wake-up controller 10 may check each of the peripheral components cited by way of example by means of a specific quiescent current IPXY, ICP, IPushbutton 2 or IPushbutton1 which, for this purpose, flows through a diagnosis resistor of the respective peripheral component. The wake-up operation according to the invention for the motor vehicle can therefore be performed depending on a read-back voltage which is dropped across the diagnosis resistor and indicates the operating state of the respective peripheral component.
To this end, the wake-up controller 10 of the on-board charger according to
The functional interaction between the individual modules can take place as follows: a first operating situation 21 of the on-board charger is present as long as the fifth module determines that no plug is plugged in. In this first operating situation 21, all of the wake-up outputs 11, 12, 13, 14 are blocked and a check is no longer made, wherein only the first wake-up output 11 forms an exception. In this first operating situation 21, the quiescent current is reduced to one tenth in comparison to conventional methods.
In a second operating situation 22 of the on-board charger, the plug is plugged in and the first module is active. In this second operating situation 22, only the quiescent current IPXY is currently flowing through the first wake-up output 11.
The same is not true in a third operating situation 23 in which not only is the plug plugged in, but the CP signal is applied to the pilot contact of said plug. In this case, the second module is active. In this third operating situation 23, the respective quiescent currents IPXY, ICP, IPushbutton2 and, respectively, IPushbutton1 flow through the first wake-up output 11, the second wake-up output 12, the third wake-up output 13 and the fourth wake-up output 14 and said wake-up outputs are checked, so that the greatest possible total quiescent current IPXY+ICP+IPushbutton2+IPushbutton1 is produced.
Finally, in a fourth operating situation 24 of the on-board charger, the plug is plugged in, the CP signal is dispensed with and the second module is active, while the first module changes the mode. Thus, only the quiescent current IPXY flows through the first wake-up output 11 and only the quiescent current ICP flows through the second wake-up output 12, while the third and fourth wake-up outputs 13 and 14 are deactivated, this leading to a considerable reduction in the consumption of quiescent current.
The benefit of the approach according to the invention can be seen in the wake-up application of current illustrated for the second operating situation 22 in
I
PXY
+I
CP
+I
Pushbutton2
+I
Pushbutton1=100 μA
Number | Date | Country | Kind |
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10 2015 102 352.0 | Feb 2015 | DE | national |